Investigation of In-Cylinder Hydrogen Mixture Formation by In-Cylinder Schlieren Observation in Hydrogen Direct Injection Engine

Atsushi Hisano･Yota Sakurai･Keisho Tanaka･Masahito Saito (Kawasaki Heavy Industries)･Satoaki Ichi (Kawasaki Motors)

In a hydrogen direct injection engine, the formation of a mixture of hydrogen and air in the cylinder is an important factor for combustion stability. Though in-cylinder CFD is utilized for grasping in-cylinder mixture formation, verification of hydrogen diffusion phenomenon in the cylinder is insufficient. In this study, the schlieren image in the cylinder is taken by the visualization engine to grasp the hydrogen diffusion, and the accuracy improvement of the hydrogen diffusion prediction in the engine cylinder analysis is examined.

Study of engine combustion in cold condition in use of methanol blended fuel

Tetsuya Ohira (Aichi University of Technology)･Keisuke Ito･Makoto Kaneko･Hidenori Fujii･Naoyuki Suda･Yoshinari Ninomiya (Suzuki Motor)

Methanol is currently under investigation as a carbon-neutral fuel for engines. However, its properties, such as its low boiling point and latent heat, pose challenges for cold-start engine combustion. In this study, we investigated a production motorcycle spark-ignited (SI) engine. Our research focused on fuel vaporization in the intake port, temperature distribution around engine components, and exhaust and crankcase gas emissions, alongside combustion stability during cold start. We found that poor fuel vaporization in the intake port were the root cause and the improvement target for degraded combustion stability following engine startup. Oil dilution may constitute a separate, critical issue.

Analysis of Fuel Properties and Spray Characteristics of Isooctane–Ethanol Blended Fuel in Port Fuel Injection Spark Ignition Engines

Koki Matsuzawa･Katsuaki Takahashi･Eriko Matsumura･Jiro Senda (Doshisha University)･Yoshiya Inoue･Kazuo Kurata (Mitsubishi Motors)

In internal combustion engines, the depletion of fossil fuels and their environmental impact have accelerated efforts toward achieving carbon neutrality, including the introduction of ethanol-blended fuels as drop-in alternatives. In this study, we investigate the effects of varying ethanol blending ratios in isooctane on azeotropic behavior and the spray characteristics in port fuel injection spark ignition engines.